Commercial mail production involves continuous, automated insertion of preprinted content, such as product advertising and marketing materials, bank statements and invoices, into envelopes for bulk mailing. The envelopes may be manufactured off site and provided in bulk for insertion. Alternatively, envelope web stock may be supplied in roll form and wrapped or folded around the insert material, followed by gluing and cutting into individual units for mailing. This method is particularly desirable because envelope roll stock is economical to obtain, store and use, and a single-line, automatic envelope production and insertion process is potentially more efficient than previous methods. However, such methods have not been fully successful for all types of business uses because the resulting mailing pieces tend to resemble folded self-mailers rather than formal business envelopes.
In addition, inserter equipment that handles inserts consisting of multiple pages is subject to work flow hesitation, while the inserter waits for the pages to be accumulated for insertion. This hesitation is exacerbated when the inserts are not uniform and the number of pages to be inserted varies from envelope to envelope. This may result in periodic stoppage of the upstream portion of the inserter while it waits for additional pages to accumulate for insertion. When such hesitation or stoppage occurs, the inserter apparatus may be temporarily unable to accept input of new envelope stock from an upstream station.
This inherent variability of inserter throughput has prevented the use of roll form envelope web stock to form window envelope stock for use in wrapper and inserter systems because the window cutting and patching operations are generally intolerant of interruption. For example, water-based window patch adhesives generally require curing over a period of time that is incompatible with automatic wrapping and insertion operations. Additionally, no process has been available to efficiently convert envelope stock by cutting or profiling and patching windows because no apparatus or method has been available to precisely apply available alternate adhesives in the open rectangular pattern necessary to completely surround the envelope window.
Accordingly, there exists a need for an improved window profiling system having a series of components that can receive a continuous web of envelope stock from a roll, align the web, measure the tension on the web and relay the information to a control system, cut window apertures and trim the seal flaps at predetermined locations to form a continuous web of window-apertured envelope blanks, apply an adhesive in surrounding relation to the window apertures, cut a web of window film to preselected lengths to form window patches, apply the window film patches in registration with the adhesive patterns on the envelope web, and control the output speed of the patched window envelope web in response to input availability data obtained from a downstream apparatus such as a wrapper, inserter or the like. This disclosure addresses this need in the art as well as other needs, which will become apparent from the following disclosure.